1. Field of the Invention
This invention pertains to rocket powered missiles, and more particularly it pertains to rocket motors having arming firing devices for preventing accidental premature ignition of the rocket motor. Most particularly, this invention pertains to mechanical devices for manually controlling the arming firing device from outside the missile structure and without the use of tools.
2. Description of the Prior Art
Rocket motors such as those used in guided missiles commonly employ an arming firing device which when in the safe position vents the combustion products of an electrically initiated squib device to the exterior of the missile to protect against premature accidental ignition of the rocket motor in the event the squib accidently fires. When in the armed position, the arming firing device directs the products of combustion of the electrically initiated squib to a booster charge which in turn ignites solid propellant fuel in the rocket motor. Prior designs have utilized an input drive shaft which extends from the exterior surface of the missile to the arming firing device which is located deep within missile structure at the forward end of the rocket motor section. This input shaft includes a key socket positioned at the outer surface of the guided missile structure. An operator uses a key to engage the key socket and move the arming firing device from the safe position to the armed position just prior to launch of an aircraft carrying the missile. The key is normally installed and retained in the key socket while the arming firing device is in the safe position. This design requires the operator to rotate and remove the key to arm the rocket motor just prior to launch of the aircraft carrying the missile and presents the possibility that a loose key may be dropped to the flight deck and ingested by the jet engine of a subsequent aircraft, resulting in severe engine damage. Further, it has been found in some cases that an armed position detent mechanism fails to positively engage and vibration may cause the arming firing device to return from the armed position to the safe position prior to missile launch from a carrying aircraft, resulting in a failure of the rocket motor to fire on command.